Satellite television receivers which decode satellite broadcast television signals for display by a television monitor are well known in the art. These receivers are commonly used in earth stations by homeowners in connection with an antenna to directly receive satellite broadcast television signals from one of a number of satellites in geosynchronous orbit about the equator. These satellite television reception only (TVRO) systems are very popular in rural areas where conventional broadcast programming is unavailable, and even in those areas where cable is not yet available as it provides an incredibly broad range of programming to choose from. These satellite receivers are generally coupled with an associated actuator which is controllable by the operator to change the positioning of the antenna from one satellite to another. Additionally, as well known in the art, each satellite has up to twenty-four transponders, each transponder being capable of transmitting a television broadcast. To increase the channel separation, every other transponder broadcasts its signal in either a vertical or horizontal polarity. Thus, all of the odd transponders of a satellite might transmit their signals of a vertical polarity while the even transponders transmit their signal in a horizontal polarity. Unfortunately, this polarization is not consistent for all satellites in that the Westar and Galaxy satellites have horizontal polarity for odd transponders and vertical polarity for even transponders.
To enhance the convenience of the receiver, remote controls are commonly available in the prior art which permit an operator to sit across the room in his favorite chair while he controls the operation of the antenna and the transponder signal being received and displayed. These remote controls generally have buttons corresponding to each of the more common satellites, volume control, azimuth adjust for correcting minor errors in the antenna, sound level, and other miscellaneous controls as might vary from manufacturer to manufacturer. For those homes having more than one television, there are many different ways in which receivers have been connected in the prior art to accommodate multiple televisions. However, there has existed problems and inconveniences with multiple receiver installations. For example, the antenna may only be pointed at one satellite at any one time. Thus, there may only be one receiver which has control of the antenna. Furthermore, as the antenna is moved from satellite to satellite, there is no means to automatically update the display at each of the other receivers so that they accurately display the correct satellite being received. There has been developed in the prior art a remote controller which may be ocated adjacent a secondary receiver and which will change the positioning of the antenna to another satellite upon request at the remote receiver, however there is no confirmation that the antenna has in fact reached the other satellite as it is a one-way link with no feedback. Furthermore, none of the other receivers are provided information as to the new satellite such that viewers have no idea which satellite is being viewed at any one time.
Still another problem which exists in the prior art results from the very fact that a wide variety of programming is available with the satellite TVRO system. Some satellites presently broadcast what some may consider to be objectionable material, and it would be desirable for some installations to be able to program one or more of the receivers to restrict the access of that receiver to certain satellites or certain transponders in certain satellites. In the prior art, an operator could lock out an entire satellite by making an entry at the actuator control (the actuator control being the controller for the antenna) and this would lock out reception from all of the transponders at a single satellite. Also, any receiver could be programmed to lock out one transponder, for example transponder number 10, but that lock-out would be independent of the particular satellite being viewed such that no transponder 10 could be viewed on any of the many satellites in orbit. Obviously, this limited selectivity on programming access is overly restrictive and insufficiently selective as there may be many unobjectionable signals which are locked out with the objectionable signals using the systems available in the prior art.
To solve these and other problems, the inventor herein has succeeded in designing and developing a combination receiver actuator unit which incorporates a microprocessor and a communication link which facilitates its connection in a network of receivers and which provides the more desirable features heretofore unavailable with the products available in the prior art. With the receiver of the present invention, a switch is provided to permit the operator to select whether the receiver is to be the master receiver of a network, or one of the slaves. The master receiver is connected directly to the antenna, and all of the slave receivers are connected to the master receiver. Therefore, the master receiver directly controls the antenna and antenna instructions entered at each of the slave units must first be communicated to the master unit before execution by the master. Furthermore, there is a communication link which interconnects the microprocessors of each of the master and slave receivers such that the slaves quiz the master as to the location of the antenna as each slave is turned on. Additionally, as the antenna is moved in response to instructions entered either at the master or at any of the slave receivers, the position of the antenna is automatically updated at each of the other slave units.
One of the more valuable features of this new receiver actuator unit is the programmable feature which an operator may utilize to lock out particular transponders of particular satellites, or even entire satellites at any slave. Furthermore, the particular transponders or satellites locked out at any slave may be different than those locked out at any other slave. To facilitate programming, all slaves may be simultaneously locked out of any particular transponder or satellite by programming entered at the master receiver.
To further enhance the lock-out programming capability, the receiver has been designed such that the remote control is necessary to change the programming. Thus, absolute security can be ensured merely by removing the remote control from physical possession of unauthorized persons. For example, the parents may desire to take the remote control with them should they leave the house for an evening to prevent a particularly adept child from reprogramming any of the receivers to gain access to the restricted transponders. This can be very important as children are oftentimes much more skilled at operating computers and other sophisticated consumer electronic devices than their parents. This programming function can be achieved by utilizing data entry buttons on the face of the receiver, and data entry buttons on the face of the remote control.
Still another feature which is available with the receiver of the present invention and which has been unavailable with receivers of the prior art is the automatic display of correct polarization for transponders on any particular satellite. As mentioned above, polarization for odd and even transponders is inconsistent from satellite to satellite. With the programmable microprocessor incorporated into the receiver of the present invention, and with the software included at the end of the Specification section herein, the receiver will automatically indicate the correct polarization for each transponder set on each particular satellite.
The principal advantages and features of the present invention have been described. However, a greater understanding and appreciation for the invention may be obtained by referring to the drawings and detailed description of the preferred embodiment which follows.